/**
 * Copyright  2017 ZTE Corporation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.openo.commontosca.inventory.core.mongo;

import java.util.function.Consumer;

import org.openo.commontosca.inventory.sdk.api.deferred.SimpleDeferredObject;

import com.mongodb.async.SingleResultCallback;

public class DeferredSingleResult<R> extends SimpleDeferredObject<R>
    implements SingleResultCallback<R> {

  @Override
  public void onResult(R result, Throwable t) {
    if (t != null) {
      this.reject(t);
    } else {
      this.resolve(result);
    }
  }

  /**
   * 
   * @param consumer
   * @return
   * @throws InterruptedException
   * @throws Exception
   */
  public static <R> R execute(Consumer<DeferredSingleResult<R>> consumer)
      throws InterruptedException, Exception {
    DeferredSingleResult<R> deferred = new DeferredSingleResult<>();
    consumer.accept(deferred);
    return deferred.join();
  }

}
